This page explains how Michael Zhang (USATT# 89100)'s rating went from 1793 to 1778 at the LYTTC Friday Pro League event from 11 Sep 2015. The links below take you to pages that describe various aspects of the rating processor.

The rating processor goes through 4 passes in order. The links take you to pages that provide detailed explanations of the calculations during each of the 4 passes.